He believed that Native Americans at the time had no rights and that they were simply put into the situation they were in since inferior to whites. So he forced them to move off their land in order to create living space for US citizens and to mine for gold and other precious metals found in the NA land. Thus causing the infamous "Trail of Tears".
B) Richard Nixon.
Nixon started the Vietnamization process, as to withdraw US troops and aid, and allow South Vietnam fight for their own country. It ended disastrously, with South Vietnam ending up in Communist rule. The US was able to pull out of the unpopular war.
hope this helps
The important natural resource in West Africa that the Songhai Empire controlled was salt.
A.) Salt mines in the sahara desert is the answer.